Road machine



y 5.3 B. T. VlG ET AL ROAD MACHINE 3 Sheets-Sheet 1 Filed Nov. 1 1949 all WQW mg w w. mm 6 Em JMPWMA B. T. VIG ETAL July 28, 1953 ROAD MACHINE 5 Sheets-Sheet 2 Filed NOV. 1, 1949 TORS lmlllll INVEN Emma! I. II A jllii;

B. T. vl ETAL ROAD MACHINE s SheetsS 5 1 J4 Ju1y2 Filed Nov. 1, 1949 INVENTQR5.

15372 f V I gydr fllzficize i WM, W @275? Patented July 28, 1953 2,646,730 ROAD MACHINE Bennie T. Vig, Morris, and Arthur H. Fischer, Alexandria, Minn.

Application November 1, 1949, Serial No. 124,884

1 The present invention relates, generally, to road machinery, and more specifically, it relates to innovations and new and useful improvements in machines which are useful all the year around in connection with the construction and maintenance of highways, parking lots, air fields, etc., which machines are capable of being towed crosscountry at normal highway speeds. Certain features of the invention make it particularly useful in connection with cross-country transportatable machines for breaking up ice and compacted snow on road and highway surfaces. Although the invention has had its greatest utility in connection with construction and maintenance of highways, parking lots, airfields, etc., where it has been used to remove ice and compacted snow, to stabilize rod surfaces, and in the application of black-top or bituminous surfacing, it will be understood that the invention is generally useful in connection with ground surface working operations and is useful for agriculture purposes.

' An important object of the invention is a ground working machine of the class described adapted to be towed on transporting wheels behind a motor vehicle for cross-country movement at normal highway speeds, and having a plurality of sets of ground working wheels wherein each ground working wheel is individually supported to permit a desired degree of independent movement with all of the ground working wheels being supported together in order to be raised and lowered as a single unit.

Another important object of the invention is a ground working machine of the class described having a pair of transporting wheels on opposite sides with a front and a rear set of ground working wheels extending across the machine, the wheels in both sets being supported 'as a single unit from a common support member which is operatively connected with a jack mechanism arranged to be driven from one of the transporting wheels.

An important object of the invention is a ground working machine of the class described having a pair of transporting wheels on opposite sides and ground working wheels intermediate the transporting wheels, the ground working wheels being supported as a single unit in a manner permitting them to be so raised or lowered in relation to the transporting wheels that: (1) the entire weight of the machine is carried by the transporting wheels; (2) the entire weight of the machine is carried by the working wheels; (3) or the weight of the machine is carried by 8 Claims. (01. 94-50) both the transporting wheels and the working wheels in any desired distribution ratio.

A further object of the invention is a ground working machine of the class described having transporting wheels on opposite sides for crosscountry mobility and having a front and a rear set of ground working wheels extending across the machine with one of the sets of ground working wheels extending in front of an intermediate arm support member with the other set of ground working wheels extending in back of the arm support, the ground working wheels in each set being uniformly spaced apart a distance equal to the width of the ground working wheels in the other set with the ground working wheels in each set aligned to track with the space between two of the ground working wheels in the other set, each of the ground working wheels' being individually connected with the arm support member by means of an arm hinged at its inner end to the arm support member and attached at its outer end to the axle fixture of a ground working wheel, each of the ground working wheels also being co-supported with a ground working wheel in the other set by means of a transverse spring extending therebetween having the free ends thereof suitably interconnected to the axle fixtures of the co-supported wheels and with each spring attached at its midpoint to a common support member extending across the machine which is adapted to be raised and lowered so as thereby to raise and lower the ground working wheels in unison.

Another important object of the invention is a ground working machine of the class described having a plurality of ground working wheels co-supported to be lowered to the ground and raised therefrom, as a unit, with each of the wheels being arranged to be independently raised oif the ground while the others remain thereon.

Another important'object of the invention is a ground working wheel for a machine of the class described having a multiplicity of prongs projecting from the rim thereof, all of the prongs being curved the same way with the radius of curvature being such as to come out of dirt or other material which is being packed by the wheels with a minimum of disturbance to the packed dirt.

Still another object of the invention is a ground working wheel for a road machine of the class described, having a shiftable weight at taehed thereto to impart a thumping or pounding action as the wheel rotates over the ground surface.

Certain other objects of the einvention will, in part, be obvious and will, in part, appear hereinafter.

For a more complete understanding of the nature and scope of the invention, reference may now be had to the following detailed description of one presently preferred embodiment thereof, and certain modifications thereof, reference bein made to the accompanying drawings, wherein:

Fig. l is a side elevational view of a ground working machine constituting a presently preferred embodiment of the invention equipped with ground working Wheels for breaking ice on highways, certain parts being removed or partly broken away;

Fig. 2 is a top plan view or the machine shown in Fig. 1 with certain parts being removed or broken away;

Fig. 3 is a rear elevational view of the machine shown in Fig. 1, certain parts being shown in sectionand certain parts being removed or broken away;

Fig. 4 is an enlarged detail view taken generally on line @-4 of Fig. 2;

Fig. 5 is a View taken on line 5-45 of Fig. 4;

Fig. 6 is an enlarged detail view, partly in section, taken generally on line 6-6 of Fig. 3;

Fig. I is an enlarged detail View, partly in section, taken generally on line 3-7 of Fig. 3;

Fig. 8 is an enlarged detail view taken on line 8-B of Fig. '7;

Fig. 9 is a side elevational view of a modified form of ground working wheel having a shiftable weight, which may be used in connection with the machine shown in Figs. 1, 2 and 3;

Fig. 10 is a side elevational view of still another type of ground working wheel particularly useful in packing dirt; and

Fig. 11 is an end elevational View of Fig. 10.

Referring now particularly to Figs. 1 to 3, the reference numeral Ill designates, generally, a road surface or ground surface working machine provided with a front set of ground working wheels II-II and a rear set of ground working wheels l2I2. The hobnailed wheels H and i2 are identical and are of the type used for breaking up ice or compacted snow of ground surfaces, and will be described below in detail in connection with Figs. 4 and 5. It will be understood that where the machine It is to be used for some purpose for which the hobnailed ground working wheels H and '12 are unsuited, they may be replaced with another type of wheel which is suitable for the work to be done.

The machine Iii has a frame, the opposite sides of which are formed by members I3-I3 and Ill-I4 (Fig. 2) which at their inner ends are welded or otherwise suitably joined to the opposite sides of a cross beam I5. Each of the side members l3 and I4 is inclined upwardly at a small angle from the center of the machine It, as shown in Fig. 1. The rear of the frame is closed by a rear cross member IE extending thereacross and provided with right-angle extensions !'-'--II at each end which fit .into the mem bers I4l i as shown in Fig. 2.

The front of the frame is closed by members IB-I8 extending inwardly at an angle from the forward ends of the members I3I3 and joined to opposite sides of a rectangular sleeve 28. A drawbar 24 extends through the sleeve 213 and is secured therein by a pin 22 extending through registering apertures provided therefor in the sleeve 2% and the drawbar ZI.

The drawbar 2I may be tilted within the sleeve 4 20 about the pin 22 and at the rear end fits in between two spaced plates 2323 secured to the front of a cross member 24. The plates 23-23 are provided with series of registering holes 25 arranged on an are so as to accommodate a pin 26 which extends therethrough as well as through two registering holes provided in the inner end of the drawbar 21. At the front end, the drawbar is provided with a U-shaped hitching member 21.

Two stub shafts 28 (Fig. 3) are suitably secured to the interior of the cross beam I5 so as to project beyond the opposite ends thereof and serve as axles for a pair of transporting wheels 31). The wheels-30 may be standard automobile or truck wheels having pneumatic tires of suitable sizeto handle the weight of the machine I0 and permit its rapid movement cross-country at ordinary highway speeds.

A shaft 3! (Fig. 3) is supported by and underneath the cross beam i5 by means of L--brackets 32-4-32 secured to the underside of the crossmember I5, as shown. The shaft 3!- serves as a support for the inner bifurcated ends of a series of arms 33-33 (Fig. 2) which support the ground working wheels II and I2. The outer or free end of each of the arms 33 carries, or has integrally formed thereon, an end portion .34 (Figs. 4 and 5,) upon which one of the working wheels Ii or I2 is supported while at the inner bifurcated ends the arms 33 are in-the form of a relatively heavy prong 35 (Fig. .2) and a relatively lighter prong 36. Each of the prongs 35 and 33 forming the bifurcated end of each arm 33 terminates in an eye or collar portion which fits over the cross support shaft M, as shown. Each of the wheels II and 82, as shown in Figs. 2 and 3, is spaced apart a distance equal to the width of the wheels, and the wheels I2 in the rear set are aligned'to track with the spaces between the wheels II in the front set;

I 0 passes over the ground, the entire ground surface from one side of the machine to the other is subjected to the action of the ground working Wheels.

Referring to Fig. 2, it will be seen that the larger prongs 35. of each of the arms 33 on one side of the shaft SI fits intermediate the prongs 35 and 38 of the arms 33 on the other side of the shaft 3 I, while the smaller prongs 36 of the arms fit in between two of the oppositely extending arms 33. The bifurcated inner ends of the arms- 33 serve to provide a. firm hinge support for each of the working wheels and prevents tilting or twisting of the arms 33 and the wheels carried on the ends thereof.

When the machine IQ is in operation, the working wheels II and I2 touch the ground and the weight of the machine may be entirely, or par-- tially, carried thereon, as will appear hereinafter. When the machine it is not in operation but is to be transported over ground, then the ported that it has a certain amount of inde-.

pendent movement without affecting the adjacent wheels. All of the wheels II and I2 are supported from and connected to a cross member 31 (Fig. 3) which at its opposite ends is provided with rectangular slide members 3838 Accordingly, when the machine- (Figs. 2 and 6) which are arranged to slide vertically between the opposite sides of upright guides in the form of inwardly faced channel sections M, 42. At their lower ends the channel sections 4| and 42 are secured to opposite sides of the cross member I5 as shown in Figs. 1 and 2 and adjacent the upper ends they are secured to the short horizontal sections 4343 (Figs. 1 and 3) fitting in between the upper ends of the inclined frame members 44-44. At their lower and outer ends, each of the frame members 44 is secured to one of the side frame members l3 or I4, as shown in Fig. 2. This arrangement permits the floating cross member 31 to be raised or lowered depending upon whether the working wheels I I and I2 are to be raised or lowered.

The manner in whicheach of the ground working wheels II or I2 is supported from the cross member 31 will be described in connection with Figs. 4 and 5 of the drawings, reference being had to Fig. 1. Each one of the front working wheels II is co-supported with one of the rear working wheels I2 (e. g. wheels H a and I2a in Fig. 2) by means of a leaf spring 45 which extends underneath the member 3'I in a generally front-to-rear direction. Each of the leaf springs 45 is secured to the member 31 at the midpoint of the spring by means of a shackle 46 as shown in Fig. 5. It will be apparent that the leaf springs 45 may be replaced with torsion type beam springs or other known equivalents.

Each of the leaf springs 45 terminates at opposite ends in an eye 41 and a link 48 is pivotally secured to each end of each leaf spring 45 by means of a removable pin 50 extending through the eye 41. At the lower end, each of the links 48 is pivotally connected to the axle fixture of one of the wheels or I2 as shown in Fig. 5. Thus, the lower end of the link 48 may be apertured so as to register with apertures provided in the spaced ears 5| and 52 (Fig. 5) projecting from the top of the end portion 34 and having a pin 53 extending therethrough. In this manner each .of the ground working wheels II and I2 is supported from the end of one of the beam type springs 45 and in turn from the cross member 31. This arrangement permits each of the wheels I I and I2 to move up and down to a certain degree, independently of the other working wheels, and thereby permits each of the working wheels II or I2 to accommodate itself to any unevenness of the ground surface or road surface which it encounters without disturbing the action of the other working wheels.

In order that the leaf springs 45 donot carry the respective working wheels II and I2 while the machine Ill is being transported across country with the result that these wheels will shake and vibrate, each of the wheels is further supported from the cross member 31 by means of a flattened tie rod 54 (Figs. 4 and 5). Each of the tie rods is pivotally connected at its lower endto the end portion 34 of one of the arms 33 by means of the .pin 53 extending through an aperture in the'end of the link 54 and registering apertures in the ears 52 and 55. At the upper ends, each of the tie rods 54 extends through a loop 58 provided therefor on the cross member 31 with the tie rods sliding easily therethrough. The upper projecting end of each of the tie rods 54 is bent at a right angle to form a projection 60 which serves as a stop which engages the loop 58 when the member 37 is raised sufficiently to take up the slack.

' In certain instances there is a need to lift one or more of the working wheels II or I2 out of action while the others remain lowered to working level. Thus, in using the machine I0 to re move ice or snow from a highway where tire tracks have become worn through so as to leave the road surface exposed along these narrow areas, with ice remaining between the bare tracks and on both sides thereof, it is desirable to raise those working wheels II and I2 which would normally follow these bare tracks, so as thereby to prevent possible injury to the bare road surface from the hobnailed working wheels. At the same time the load on the remaining wheels which break up the ice and compacted snow is increased to the extent of the load normally carried by the suspended wheels. In another situation, it may be necessary to use the machine III to work a strip of ground surface which is narrower than the full width of the sets of Working wheels II and I2, with raised areas or borders on both sides of the narrow strip. In this situation it is desirable to be able to suspend some of the working wheels on both sides of the machine It! so as to in effect reduce its effective width.

The independent suspension of the working wheels I I and I2 is provided for by a pin-receiving aperture or hole 56 in each of the tie rods '54 at a suitable distance from the upper end thereof, as shown in Figs. 4 and 5. When it is desired to raise any one of the working wheels I I or I2 to take it out of action, the link 48 associated With that particular working wheel is disconnected from the associated leaf spring 45 by removing the pin 56, and then the wheel is raised so as to bring the aperture 56 in the tie rod 54 above the loop 58, and a retaining pin is then inserted in the aperture 55 so as to hold the wheel in this raised position.

Although the wheels II and I2 may themselves have considerablev weight, it is usually desirable to load them with extra weight, and for this purpose the machine I 0 is provided with front and rear ballast or Weight boxes 6| and 62, respectively (Fig. 1). Each of the boxes 6| and 62 is supported at its opposite ends from the upwardly inclined frame members 44 by means of links 6363, each of which is pivotally connected at its lower end to a lug 6'4 projecting from the adjacent frame member 44 and is pivoted at its upper end on a pin 65 carried on the adjacent side of the box 6| or 62.

Along their inner sides, each of the boxes 6| and 62 is pivotally connected to a series of cross links 65-456 as shown in Figs. 2 and 6. At their mid-points the links 65 ride on the top of the cross member 31. The inner sides of the boxes BI and 62, as shown in Fig. 6, are provided with lugs .ii'l-e-fil having apertures which are adapted to be aligned with apertures in the opposite ends of the links 66, with pins 68 extending therethrough. By means of this pivot type connec-, tion between the inner faces or sides of the boxes 6| and 62 and the links 55-66, the cross member 3'! may be raised and lowered While the weight contained in the boxes is continuously applied to the cross member 37. It will be seen that the total weight carried on the cross members 31 is in turn uniformly distributed through the leaf springs 45 to each of the Working wheels II and I2.

One of the important and advantageous features of the present invention incorporated in the machine it! is the ease and convenience with which the machine H) may, on the one hand, be placed in condition for cross-country transporta tion on the transporting wheels .30 and then, when in position to be put to use, may, on the other hand, be placed in condition for operation with the working wheels I I and i2 lowered. The convenient conversion from operative to inoperative transporting condition requires that jack means be provided for quickly raising and lowering the gangs or sets of wheels II and I2. By providing a jack which is ar'anged to be driven by one of the transporting Wheels the machine It} may be easily handled by a single operator, usually the truck or tractor driver.

The jack mechanism for raising and lowering the cross member 37 and in turn the working wheels II and I2 is operated off one of the transporting wheels 39, such as the one which is provided with a ring gear '29, Figs. 1 and 3. Within the ring gear and adapted to be alternately intermeshed therewith is a pair of pinion gears Ii and I2 shown at enlarged scale in Figs. 7 and 8. The pinion gears II and 22 are mounted on shafts 5? and 59, respectively, journaled in a pair of spaced, vertical plates 53-78 which stand up integrally from a slide member 69 which rests on, and is slidable over, a fiat plate M which is secured or mounted on top of the cross frame member I5. The plate 54 has an L-shaped flange E8 integrally formed along one side thereof and a removable L-shaped flange d9 bolted along the opposite side thereby permitting removal of the slide 69 for cleaning or repair.

The slide 69 is adapted to be moved across the support I4 in opposite directions by means of a pair of shifting levers l5 and IE. The lever 15 is pivoted at its lower end to one end of the plate is as indicated at Ti and the lever I5 is connected to one end of the slide 89 by means of a link i8 pivotally pinned to the lever I5 as indicated at 80 and pivotally pinned to the slide -59 as indicated at 8 I.

The other operating lever I8 is pivoted at a point somewhat above its lower end as indicated at 82 to an upstanding post member 83 which extends upwardly from the adjacent end of the support platform l4. At its lower end, the lever I6 is pivotally connected at 84 to an ear projecting from the adjacent end of the slide 69.

It will be seen that when the lever I5 is pulled to the left (which is toward the front of the machine Ill) the pinion gear 1| will be shifted so as to intermesh with the ring gear It. When the rear lever It is moved to the left, it will shift the pinion gears to the rear so that the pinion gear I2 intermeshes with the ring gear I0. Only one of the pinion gears II or I2 can intermesh with the ring gear 710 at one time. In order normally to hold the pinion gears II and 12 in a neutral position, springs 85 and 85 are secured on opposite sides of one of the levers, e. g. 75, so as to hold the gears II and I2 in the neutral position whenever the levers I5 and I6 are released.

The shaft 51 on which pinion gear II is mounted projects through the rear plate I3 and carries one section 8! of a universal joint as shown in Figs. 3 and 8. The other section 88 of the universal joint is attached to an extensible drive shaft 89 which at its upper end carries one section 53 of a universal joint, the other section of which is indicated at El! and is attached to a jackscrew 92. The extensible drive shaft has a square tubular section attached to the universal joint section 88, and a square rod section which fits telescopically in the tubular section and which is attached to the universal joint section 90.

The jackscrew 92 extends between the opposite halves or sections of a scissors-type jack, one section of which is indicated at 93 and the other section of which is indicated at 94. Referring to Fig. 3, it will be seen that each of the jack sections 93 and 94 at its joint carries a nut 95 and 96, respectively, through which the oppositely threaded portions of the jack driving screw 92 extend. Each of the arms of each section 93 and 9 1 is pivotally connected to each of the nuts 95 and 96. At their upper ends, the upper arms of the sections 93 and 94 are connected to opposite sides of the cross member 31 by means of pins E and Iii! extending through registering apertures provided therefor- At their lower ends, the lower arms of sections 93 and 94 are pivotally connected to opposite sides of the stationary cross member or beam I5 by means of pins I04 and I05 extending through registering apertures provided therefor.

It will be seen that when the drive shaft 89 is rotated in one direction the scissor sections 93, 96 will tend to straighten out thereby lifting the cross member 3], whereas when the screw 92 is turned in the opposite direction, the scissors section will be folded so as to lower the support member 31.

Th hobnailed working wheels II and I2 may be replaced with other types of working wheels so that the machine 50 may be put to other uses than breaking ice and snow from roads and like areas. In this way, the machine Ill may be utilized to advantage all year round. Thus, in the summer time the machine I0 may be used for bituminous or black-top surfacing by replacing the working wheels I i and I2 with working wheels equipped with pneumatic tires or flat steel rims.

In Fig. 9 of the drawings a modified form of the working wheel III) is shown having hobnails HI extending from the tire portion thereof. weight member [I2 is secured in fixed position on one side of the wheel III] while a member H3 of equal weight, provided with arouate slots H4, ilii, is mounted on the other half of the wheel and secured by clamping bolts H6, H1. The slots H4 and H5 permit the weight section II3 to be secured in a position where it does not counter-balance the stationary weight H2, thereby unbalancing the wheel III]. When this type of wheel is in place on the machine II), it gives a pounding or thumping action which assists in the breaking or crushing of the ice or similar hard material on a road surface. This pounding action may also be obtained by eccentrically mounting the wheels II or I2.

In Figs. 10 and 11, still another form of ground working wheel is shown and indicated, generally, at I20, which oifers unique advantages when the machine Ill is used to pack down loose dirt, sand, and the like. The wheel I20 has a plurality of curved prongs I2I projecting from the rim thereof with the plane of the prongs being parallel to that of the wheel I20. When the wheels I20 are mounted on the machin II] so as to turn clockwise as the machine is towed, the prongs iii serve to pack down dry dirt, sand, and the like and the prongs come out of the dirt without disturbing the top surface. The prongs may, for example, be suitably formed from one inch diameter spring steel rods.

The machine I 0 operates in the following manner: With the working wheels II and I2 supported in the raised condition, the machine I0 is in condition to b transported cross-country behind a towing vehicle such as a truck or tractor. When the machine I0 arrives at the location i9 whereit is tobe put into use, the operator from his position in thetruck' or tractor pulls the lever l-forward by means of arope attached, thereto, thereby shifting the pinion gearor wheel H into mesh with the ring. gear 70.; The. towing .vehicle is allowed tocreep or move slowly ahead and thisturns the pinion wheel H in a counterclockwise direction and results in the jackscrew 92 also turning in a counterclockwise direction. The directions of thethreads on the two threaded sections of the jackscrew 92 are such that when the screw92 is turned in a counterclockwis direction the jackis collapsed, and the cross member 31 is lowered. As the member'31 is lowered, a point is reached where the projections 60 on the tie ro'ds' 54 no longer engage th loops 58 and the Wheels! land 12 thenbecome supported by theleafsprings 45. When the wheels H and I2 touch the ground the jackis allowed to be further collapsed so that the weight of the machine it istransferred, to the desireddegree from the transporting wheels 30 to the working wheels H and 12. In this way, the entire weight of the machine it may be transferred to the wheels II and I2, or any desired portion of the weight may be transferred thereto. The machine It) having thus been placed in operating condition with the working wheels ll, I2 on th ground, the lever I5 is released and the pinion gears H and 12 assume the neutral position.

The driver then proceeds to pull the machine [0 over the ground surface to be worked, such as a highway from which ice is to be taken. It will be seen that all of the weight applied to the cross support member 31 by means of the ballast put in the boxes BI and 62 will be transmitted evenly through the springs 45 to the working wheels I: and I2.

The ability to regulate, by means of the jack mechanism, the amount of load borne by the working wheels H and I2 is a very desirable feature of the machine If! since often only a fraction of the full weight of the machine If) is called for to produce the proper or safe pressure of the working wheels on the ground surface. For example, when th machine if) is used to break a thin coating of ice from a black-top road, injury to the road surface can easily result from excessive pressure.

When the driver desires to remove the machin from one locality and take it cross-country to another, be pulls the rope from its forward position which is attached to the lever 15 and thereby brings the pinion gear l'2 into mesh with the ring gear iii. He then allows his towing vehicle to move slowly forward which results in the turning of the pinion gear II in a clockwise direction and the simultaneous driving of the jackscrew 92 in a clockwise direction. This causes the nuts 95 and 96 to move toward each other and causes the jack sections 93 and 94 to straighten up, thereby raising the support member 31. During the first portion of the elevation of the cross support member 31, th weight of the wheels II and i2 is carried by the leaf springs until the loops 58 on the cross member 31 engage the projections '69 on the tie rods 54. At this point the weight is taken off the leaf springs 45 and is sustained by the tie rods 54. The driver allows the jack mechanism to raise the wheels H and E2 to the desired extent and then releases the rope allowing the pinion gears II and 72 to return to the neutral position.

l'he amount of friction in the jack elevating mechanism, due principally to the friction be- '10 tween'the jackscrew 92 and nuts 95'and 96, is sufficient to maintain the jack in the position in which it is left, anda locking mechanism is not required.

Sinc certain changes may be made in the foregoing construction described above and shown in the accompanying drawings, without departing from the, scope or spirit of the invention, it is intendedthat all matterthus shown or described shall be interpreted as illustrative and not in a limiting. sense.

What-is claimed as new is; 1. In a ground working machine of the, class described having a main frame and transporting wheels on opposite sides of said frame, in com bination, front and rear sets of ground working wheels disposed between opposite sides of said frame, a horizontal arm support member extending between said sets of ground working Wheels and supported at opposite ends by said frame, an individual support arm for each of said ground working WIhGBlS, each of said'support arms being swingably mounted at its inner end on said arm support member for swinging in a vertical plane and each of said support arms at its outer end being attached to the axle mounting of one of said ground working wheels, said support arms extending alternately on opposite sides of said arm support member with said front set of ground working wheels being mounted on the support arm extending on the front side of said arm support member and said rear set of ground working wheels being mounted on the support arms extending on the rear side of said arm support member, the ground working wheels in said rear set being staggered with respect to the ground working wheels of said front set, a horizontal common support member disposed over said arm support member from which said ground working wheels are suspended, means for adjustably positioning said common support member at different elevations over said arm support member whereby when said common support member is fully raised said ground working wheels will be lifted off the ground and when said common support member is fully lowered said transporting wheels will be lifted off the ground, yieldable compression link-age means individually interconnecting the axle mounting of each of said ground working wheels with said common support member whereby a compression load may be yieldably transmitted between said common support member and said ground working wheels, and tension linkage means interconnecting said ground working wheels and said common support member therefor so that said wheels will be lifted from the ground when said member is fully elevated.

2. The combination called for in claim 1 wherein said means for adjustably positioning said common support member is jack means interconnected between said common support member and said frame.

3. The combination called for in claim 1 wherein said ground working wheels are unbalanced thereby imparting a pounding action as the machine is pulled over the ground surface with the ground working wheels in engagement therewith.

4. The combination called for in claim 1 wherein a tie rod is connected at one end to said axle mounting of each ground working wheel and connected at the other end to said common support member, each of said tie rods having a slip connection at one of its ends and stop means to take up the slippage when the common sup- 11 port member is raised sufficiently to raise the ground working wheels above the ground level.

5. The combination called for in claim 1 wherein said means for adjustably positioning said common support member comprises jack means operatively interconnected between said main frame and said common support member whereby said ground working wheels may be unitarily raised above and lowered to the ground level.

6. The combination called for in claim 1 wherein a jack operating mechanism is operatively interccnnected between said jack means and one of said transporting wheels.

7. The combination called for in claim 1 wherein a ballast box is disposed over each of said front and rear sets of ground working wheels, support means for each of said ballast boxes extending between the outer portions of said boxes and said machine frame with each of said support means being pivotally connected at least at one end to one of said ballast boxes or to said frame, and link means pivotally interconnecting 12 adjacent sides of said ballast boxes and resting on the top of said common support member whereby the weight of each of said ballast boxes and its contents is continuously applied to said common support member.

8. The combination called for in claim -1 wherein said yieldable compression linkage means include leaf springs.

BENNIE T. VIG. ARTHUR H. FISCHER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date I 1,196,464 Lee l-- Aug. 29, 1916 1,673,184 Cady June 12, 1928 1,699,487 Killik Jan. 15, 1929 2,270,390 Summers Jan. 20, 1942 2,407,965 Smith Sept. 17, 1946 2,484,285 Greiner Oct. 11, 1949 

